This invention relates to aerosol dispensers in general, and more particularly, to a cap and activator button dispensing assembly for use on an aerosol dispenser.
Aerosol dispensers are well known in the art and have been widely used since the early 1950s. Typically, an aerosol dispenser is a container or metal can containing a material under gaseous pressure. A valve stem extends out of the container from a valve connected to a dip tube that extends down into the can. Generally, a button or activator having a nozzle formed therein is mounted on the valve stem and downward pressure of the activator button opens the valve allowing dispensing of the material.
Generally the can is filled with the material to be sprayed and the propellant or compressed gas. The valve is normally held shut by the pressure in the can and by a spring directly below the valve stem. When a push-button or activator is pressed, it forces the valve stem down in its housing uncovering a small hole which leads up through the stem to a dispensing nozzle in the button or activator. This allows the product to be forced up the dip tube, through the valve and valve stem and out the nozzle by the gas pressure in the container. The nozzle can be shaped to give a spray or continuous stream or widely opened to allow dispensing of a foam or a viscous material. Aerosol dispensing cans have wide applications and are used in such diverse products as hairspray, deodorants, shaving cream, bug spray, paint, and even food products such as cheese spreads. One of the more recent uses for aerosol cans is for the dispensing of personal self-defense products, such as mace or red pepper spray. A small aerosol container of mace can be carried by an individual and used to spray the face and eyes of an assailant.
In most prior art aerosol dispenser assemblies, the push-button nozzle is simply a small, plastic cap with a dispensing orifice that is slipped onto the valve stem and held in place by friction fit. A cap or lid must be placed over the end of the container to cover the nozzle button. To use the container, the cap is removed to provide access to the button. The cap is necessary for storage or transport and to prevent accidental or unwanted discharge of the material due to accidental activation of the button. However, a container assembly having a separate lid is not acceptable for use on a dispenser for a personal protectant spray such as mace. Removal of the lid to reach the activator button would require extra time which is not available in an emergency situation. Furthermore, this type of nozzle does not provide for safety locking to prevent accidental discharge of the product. Therefore, it is an advantage to have a cap and activator assembly that does not require a separate, external cap or lid.
Several prior art devices have used a combination cap and button assembly to prevent accidental or unwanted operation of the button and discharge of material. For example, U.S. Pat. No. 3,484,023 to Meshberg, discloses a dispensing cap assembly comprising an outer housing which slideably supports a dispensing button which can rotate within the housing. When the dispensing button is moved to a dispensing position, the button can be depressed to activate the valve. When the button is moved to a closed position, the button cannot be depressed, thereby effectively preventing operation and discharge of material.
There are several notable disadvantages to this design. For example, there is no structure to retain the button portion within the housing. That is, during manufacture, the housing and button are molded separately. During assembly, the housing is mounted over the end of the aerosol container. The button portion is then heated by boiling in water and inserted into the housing so that the button portion seats on the valve stem. As the button portion cools, it contracts and is retained on the valve stem by a tight friction fit. This particular type of assembly is labor intensive and time consuming to assemble.
Furthermore, assemblies of the prior art type can fail during use. For example, the user must manipulate the button from a non-dispensing to a dispensing position. When the user exerts rotational pressure on the guide member or tab there is often an upward pressure exerted as well. This upward pressure of the thumb or finger can force the button off the valve stem and out of the housing. If the assembly is employed on a personal protectant spray can, for example, this failure can have disasterous consequences. Furthermore, prior art buttons can come apart in a pocket or handbag if the button portion is bumped, pushed or if the button is caught on another object during withdrawl from the handbag or pocket. Moreover, if the user tries to reattach or reassemble the button, the valve can be inadvertently activated and product discharged. Also, since the button portion is retained by friction, the force of this friction fit can sometimes be overcome by the propellant pressure as the material enters the button and nozzle for dispensing and the button portion can be forced off the valve stem and out of the surrounding housing, causing valve failure and product waste.
It is therefore an object of the invention is to provide an aerosol container cap and activator button assembly having a retention means for securing the activator button within the cap housing to prevent the button from being forced off the valve stem and out of the cap housing by the user or by aerosol pressure.
Another object of the present invention is to provide an aerosol container cap and activator button assembly wherein the cap housing portion is retained on the aerosol container and the button portion is mounted on the valve stem, yet retained in its position by a retention means holding it to the cap housing, thereby retaining the button on the valve stem by a positive retention means as well as by a friction fit.
It is another an object of the present invention to provide an aerosol container cap and activator button assembly that can be moved from an open to a closed position to prevent accidental discharge of the contents of the container.
Still another object of the present invention is to provide an aerosol container cap and activator button assembly that can be molded in two pieces but assembled prior to mounting on a container, thereby eliminating the step of heating and mounting the button portion separately.
A still further object of the invention is to provide an aerosol container cap and activator button assembly that is easy and economical to manufacture, requires a single step to attach to an aerosol container, and is well suited for its intended purposes.